Sounds like your seat back angle has changed.......I needed to tie a half knot in the tail end of the nylon line so the back did not "slip aft".This kept me from holding on to the cockpit side carrying handles.Lastly, I found that doing "full strokes" was not an advantage.....shorter, rapid strokes moved the kayak quicker/faster if needed.

The only time I really grab the handles and hold on is in rough water...other times I either hold my arms up to my life vest or have a fishing rod in one hand the the tiller handle in the other. It is however very easy to add additional handles if you find you need it relocated, I added a Ocean Kayak handle behind the seat for easier carrying on land. Very simple measure, drill and rivet procedure. Good luck in your search of fixes.

On the subject of the carrying handles, but not particular to holding a handle while pedaling, I have an observation. If I pick up the 2009 Outback by the two carrying handles, the rear of the kayak tilts downward to the ground. To carry the Outback short distances, I put a short tie-down strap through the rear scupper hole and use the strap and one carrying handle (either one) to keep the Outback (which is now one side towards the ground) parallel to the ground while moving it. Just an observation that simmers in the back of my mind.